Angina and Heart Attacks

Introduction

Angina and heart attacks kill more men in the UK than any other single disease, and six times more women than breast cancer. The cause is coronary artery disease, a disease that is common all over the western world and is an increasing health problem in developing countries. Most people will know a relative or a friend who has had a heart attack, often without warning.

At a basic level the disease that causes angina and heart attacks is simple to understand:

• The heart is a powerful muscle that maintains life by pumping blood round the body.

• To function properly the heart requires a good blood supply and this is provided by the coronary arteries.

• Disease of the coronary arteries interferes with the normal blood supply of the heart and can lead to angina and heart attacks.

This book is about how and why coronary artery disease occurs, how it affects the heart, and what can be done to prevent and treat it.

What’s in a name?

The general name that we give to the disease causing angina and heart attacks is coronary heart disease, or CHD for short. The underlying cause is atheroma, a disease in which the coronary arteries become gradually clogged with fat. The narrowed arteries lead to the symptom of angina and, if the arteries block completely, to a heart attack. Over the last 50 years medical research has discovered a number of important factors responsible for CHD and there are many ways in which we can prevent it.

Coronary artery disease can cause a number of problems for the heart, all the result of insufficient oxygen reaching the heart muscle. The following are the most common.

Angina

A pain in the chest that comes on typically when exercising; this can include everyday physical effort, not just activities such as aerobics or jogging! The pain gets better when you rest.

Heart attack (myocardial infarction or MI)

Life-threatening chest pain when the artery blocks completely, resulting in damage to an area of heart muscle.

Other conditions that are often the result of coronary heart disease include the following.

Heart failure

The heart muscle is damaged so that it cannot pump enough blood to the rest of the body, leading to breathlessness and fluid retention.

Irregularities of heart rhythm (arrhythmias)

Irregular beats can cause palpitations but are sometimes serious enough to stop the heart beating altogether.

Other causes of heart problems

Not all heart disease is the result of coronary artery disease, but it is far and away the most common cause in the UK. Other heart problems include the following.

Congenital heart disease

Abnormalities of the heart that are present at birth, such as a hole in the heart.

Cardiomyopathies

Diseases that damage the heart muscle directly rather than the coronary arteries.

Valvular heart disease

Damage to any of the four valves that control blood flow in the heart.

Who gets heart disease?

The number of people who get CHD varies enormously from one country to another. We are all used to the idea that certain diseases are more common in one country than another, yet we don’t usually see our own country in the same way. But if we were looking down on the Earth from another planet we would be as struck by the high rates of heart disease in the British Isles as we would be by malaria in the tropics.

A disease of affluence

In general, CHD is traditionally thought of as a disease of affluence and is much less common in developing countries such as Africa. It is most common in northern Europe, North America and Australasia. It does seem to be related in some way to lifestyle, because when people move from the developing countries to a more affluent culture they get CHD much more often than they would have done at home. This is particularly noticeable among immigrants from the Indian subcontinent who come to the UK and who are then even more likely to develop CHD than people who are born here.

Regional variations

In Europe there are major differences between countries and even within one country. In southern Europe, CHD is generally much less common than in the UK and Scandinavia – and this may be one of the reasons for the popularity of the Mediterranean diet. Many people believe that this way of eating – with lots of fresh vegetables, salad, fruit and fish and relatively little red meat or dairy produce – can help protect against heart disease.

In the UK itself there are also large variations between regions; the highest rates are in what were the old areas of industrialisation – northern England, Scotland, Wales and Northern Ireland.

When was CHD first recognised?

Although descriptions of CHD date back to the classical world, it was not recognised to be a common disease until after World War II. The rate of heart disease, particularly among young men, rose alarmingly. It peaked in the USA and Australia in the 1970s and in the UK in the mid-1980s and has been falling steadily in these countries ever since. Unfortunately, rates of CHD are rising rapidly in eastern Europe, with countries such as Russia and the Baltic states now heading the league table. There are also worrying trends in Asia where affluence has also brought with it a sharp rise in CHD.

In spite of the improvements in the UK in recent years, CHD remains a serious public health problem. It is increasingly common in elderly people and four times more common in men than in women. In young men it is the most common cause of death after accidents.

What are the probable causes of CHD?

Why is CHD so common in the UK? No one knows for sure, but diet, smoking, lack of exercise and social deprivation seem likely culprits. However, poverty, lack of exercise and smoking also occur in other countries where the risk of CHD is much lower, which is why there is so much focus on the British diet as a potential cause. In the UK there are particular concerns at the moment about the rising numbers of people who are overweight, even as children, and unless this is corrected we may see a rise in CHD again.

New treatments for CHD

The last 10 years have seen enormous advances in the treatment of CHD. There are drugs such as the ‘clot busters’ used after a heart attack, better drugs for angina and powerful cholesterol-lowering drugs, to name just a few. And we have come to understand the value of some of the older drugs such as beta blockers and aspirin. Not only can these help in relieving symptoms such as pain, but they can also slow down or even reverse some of the changes seen in the disease.

The biggest advances, however, have been in the use of surgery and angioplasty. Bypass surgery (CABG – often pronounced as ‘cabbage’! – which stands for coronary artery bypass graft) can transform the life of an angina sufferer and can reduce the risk of further heart attacks.

Angioplasty – a technique in which tiny balloons are used to stretch narrowed or blocked arteries – can also be very effective, especially now that fine wire stents (or internal supports) are used to keep the arteries open.

This is all good news for anyone who has already developed heart trouble but our priority as a country should be to tackle the underlying reasons why CHD is so common and try to stop so many people getting it in the first place.

KEY POINTS

• CHD is still one of the most common causes of death in the UK for both men and women

• There was an epidemic of CHD in the twentieth century, which is now declining in the UK but rising in countries in eastern Europe and Asia

• New treatments, including bypass surgery, have helped a lot, but prevention remains better than cure